Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Schedule of Equity Method Investments [Line Items]
Investment in joint ventures at beginning of the period	$ 47,941
Earnings from joint ventures	4,787
Investment	(5,013)	$ 0
Distributions received from joint ventures	3,300	$ 5,540
Foreign currency translation adjustment	(489)
Investment in joint ventures at end of the period	53,952
WMES
Schedule of Equity Method Investments [Line Items]
Investment in joint ventures at beginning of the period	34,183
Earnings from joint ventures	4,882
Investment	(5,013)
Distributions received from joint ventures	3,300
Foreign currency translation adjustment	0
Investment in joint ventures at end of the period	40,778
CASC Willis
Schedule of Equity Method Investments [Line Items]
Investment in joint ventures at beginning of the period	13,758
Earnings from joint ventures	(95)
Investment	0
Distributions received from joint ventures	0
Foreign currency translation adjustment	(489)
Investment in joint ventures at end of the period	$ 13,174

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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